Package for shipping stackable articles

ABSTRACT

A package for stackable articles, such as egg cartons, produce containers, plates, food trays and the like, includes substantially tray-shaped top and bottom caps. Sandwiched therebetween are stacks of the articles arranged vertically or horizontally to form a desired array between the top and bottom caps. Sheet material wraps around the array and at least partly around the top and bottom caps to enclose the array securely between the caps.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the packaging arts and specifically to the packaging of light, relatively fragile articles which have been molded from lightweight materials, such as sheets of polystyrene foam.

2. Description of the Prior Art

Light, relatively fragile containers of a variety of types, such as food containers, egg cartons, plates, trays and the like, are manufactured by the millions, and shipped to food packagers in such numbers for packaging eggs, fruits, vegetables and meats for retail sale. The containers in question are often molded from polystyrene foam sheets, and are therefore quite light and relatively fragile.

In the prior art, containers of this type have been stacked and arranged in some desired array for shipment on pallets, the generally wooden frames which can be transported by a fork lift. The stacks of containers are then wrapped with film material, such as shrink-wrap or stretch film, with the film material at least partially enclosing the pallet making it a part of the resulting package.

In such a situation, the pallet makes up a considerable portion of the size and weight of the package. While the stability of the package may be significantly enhanced by the sturdy wooden pallet, the presence of the pallets makes it risky to stack the packages atop one another in a warehouse or truck as they may easily damage the fragile articles in the packages beneath due to their weight. Moreover, the pallets take up a great deal of room in a loaded truck, perhaps as much as 12% of the volume of the truck, reducing the number of the articles that could be included in a single truckload, and making it difficult to fill the truck completely.

The present invention provides a solution to this problem of the prior art by eliminating the requirement for a pallet.

SUMMARY OF THE INVENTION

Accordingly, the present invention is a package for stackable articles, such as the relatively fragile containers identified above. The package comprises a top cap and a bottom cap, which are substantially tray-shaped. Specifically, the top and bottom caps each have a base with side and end walls extending therefrom.

The package includes a plurality of stacks of the articles of interest. The stacks are arranged in a desired array on the bottom cap either vertically or horizontally. That is, the stacks may be either standing on or lying on and over the bottom cap.

The top cap is disposed atop the array and oriented toward the bottom cap so that the top and bottom caps partly enclose the array.

Sheet material, such as, for example, shrink-wrap or stretch film, wraps the array and at least partly wraps the top and bottom caps, thereby enclosing the array securely between the top and bottom caps.

In a preferred embodiment, the top and bottom caps are folded from blanks cut from stiff sheet material, such as corrugated board or plastic.

The present invention also includes a method for making a package of stackable articles. The method comprises the step of providing a top cap and a bottom cap for the package, the caps being as described above.

The method further includes the steps of forming a plurality of stacks of the stackable articles, and of arranging the plurality of stacks in a desired array on the bottom cap. Finally, the method also includes the steps of disposing the top cap atop the array, and of wrapping around the array and at least part of the top and bottom caps with sheet material to enclose the array securely between the top and bottom caps, thereby forming the package.

The present invention will now be described in more complete detail with reference being made to the drawings identified below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a blank from which the top and bottom caps of the present package are assembled;

FIG. 2 is a perspective view of a top or bottom cap when assembled; and

FIG. 3 is a perspective view of a package of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning now to these figures, FIG. 1 is a plan view of a blank 10 which is cut from a stiff material such as corrugated board or plastic sheet, and creased and folded to form the top or bottom cap for the package of the present invention. The blank 10 defines a base panel 12, a first pair of opposed side wall panels 14 with tuck-in end flaps 16 and a second pair of double-thickness wall panels 18.

To assemble the tray-shaped top or bottom cap 20 shown in the perspective view thereof given in FIG. 2, the first pair of opposed side wall panels 14 are folded upward about creases 22 with the tuck-in end flaps 16 being folded inwardly about creases 24. Then, the second pair of double-thickness wall panels 18 are folded upward about creases 26, and subsequently about double creases 28 to enclose tuck-in end flaps 16 within double-thickness end walls 30 by engaging edge tabs 32 in correspondingly shaped slots 34. In this manner, the tray-shaped top or bottom cap 20 is formed.

FIG. 3 is a perspective view of a package 40 of the present invention. The package 40 comprises tray-shaped top and bottom caps 20. The walls of the bottom cap 20 are upwardly oriented, while those of the top cap 20 are downwardly oriented.

The package 40 is typically used for shipping light, relatively fragile articles, especially those which have been molded from sheets of polystyrene foam. Typically, the package 40 contains hundreds of such articles, which are stacked in a compact arrangement, sandwiched between the top and bottom caps 20 and wrapped in a sheet material, such as a shrunk-wrap or stretch film 42.

The present invention is not limited to any specific article of the above general type. For example, the package 40 shown in FIG. 3 contains egg cartons 44 of the variety familiar to anyone who has ever bought eggs in a retail outlet. The egg cartons 44 are stacked following molding from polystyrene foam to a height equal to an inside dimension (length or width) of the top or bottom cap 20. Such a stack 46 may easily contain hundreds of egg cartons. Several such stacks 46 are then placed next to one another in the bottom cap 20. Preferably, the combined width of the several stacks 46 is equal to the other inside dimension (length or width) of the top or bottom cap 20. One or more additional layers of stacks 46 are then built up upon that in the bottom cap 20 to form a package 40 of a desired height and containing a desired number of egg cartons 44. When the desired height is reached, a top cap 20 is placed over the top row of stacks 46, thereby sandwiching the stacks of egg cartons between the two caps 20. Sheet material, such as shrunk-wrap or stretch film 42, is then used to enclose the top and bottom caps 20 and the stacks 46 of egg cartons 44 therewithin.

As implied above, there is no intention on the part of the inventor to limit the present invention for use in shipping egg cartons molded from polystyrene foam. It will be apparent to those of ordinary skill in the art that the package of the present invention may be used to ship nestable or stackable articles of many kinds made from polystyrene foam or from other materials. Egg cartons, produce containers, plates and food trays are but a few of the many kinds of articles. Moreover, the articles need not be stacked horizontally as shown in FIG. 3, but could alternatively be stacked vertically between the top and bottom caps. In such a case, a plurality of stacks are set out in an array which fits within the inside dimension of the bottom cap 20.

Modifications to the above would be obvious to those of ordinary skill in the art, but would not bring the invention so modified beyond the scope of the appended claims. 

1. A package for stackable articles, said package comprising: a top cap and a bottom cap, said top and bottom caps being substantially tray-shaped and having a base with side and end walls extending therefrom; a plurality of stacks of said articles, said stacks being arranged in a desired array on said bottom cap and said top cap being disposed atop said array, said top and bottom caps being oriented toward one another to partly enclose said array; and sheet material wrapped around said array and at least partly around said top and bottom caps to enclose said array securely between said top and bottom caps.
 2. A package as claimed in claim 1 wherein said top and bottom caps are folded from a blank cut from stiff sheet material.
 3. A package as claimed in claim 2 wherein said stiff sheet material is of plastic.
 4. A package as claimed in claim 2 wherein said stiff sheet material is of corrugated board.
 5. A package as claimed in claim 1 wherein said stacks are oriented horizontally to form said desired array.
 6. A package as claimed in claim 1 wherein said stacks are oriented vertically to form said desired array.
 7. A package as claimed in claim 1 wherein said articles are molded from polystyrene foam sheet material.
 8. A package as claimed in claim 1 wherein said articles are selected from the group consisting of egg cartons, produce containers, plates and food trays.
 9. A package as claimed in claim 1 wherein said sheet material is of plastic.
 10. A package as claimed in claim 1 wherein said sheet material is shrink-wrap film.
 11. A package as claimed in claim 1 wherein said sheet material is stretch film.
 12. A method for making a package of stackable articles, said method comprising the steps of: providing a top cap and a bottom cap for said package, said top and bottom caps being substantially tray-shaped and having a base with side and end walls extending therefrom; forming a plurality of stacks of said stackable articles; arranging said plurality of stacks in a desired array on said bottom cap; disposing said top cap atop said array; and wrapping around said array and at least part of said top and bottom caps with sheet material to enclose said array securely between said top and bottom caps, thereby forming said package.
 13. A method as claimed in claim 12 wherein said providing step includes the steps of: cutting a blank for each of said top and bottom caps from stiff sheet material; and folding said blank to form each of said top and bottom caps.
 14. A method as claimed in claim 12 wherein, in said arranging step, said plurality of stacks are disposed horizontally on said bottom cap to form said array.
 15. A method as claimed in claim 12 wherein, in said arranging step, said plurality of stacks are disposed vertically on said bottom cap to form said array.
 16. A method as claimed in claim 12 wherein said sheet material is shrink-wrap film and further comprising the step of heating said shrunk-wrap film to shrink said film after said wrapping step.
 17. A method as claimed in claim 12 wherein said sheet material is stretch film 